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101.
The management of fulminant ulcerative colitis   总被引:4,自引:2,他引:4       下载免费PDF全文
This paper describes the management of 23 patients with fulminant ulcerative colitis, 22 of whom had early surgery when medical treatment was unsuccessful. There were two deaths, a mortality of 9%.  相似文献   
102.
Basis of the gabamimetic profile of ethanol   总被引:2,自引:0,他引:2  
This article summarizes the proceedings of a symposium held at the 2005 Research Society on Alcoholism meeting. The initial presentation by Dr. Wallner provided evidence that selected GABA(A) receptors containing the delta subunit display sensitivity to low intoxicating ethanol concentrations and this sensitivity is further increased by a mutation in the cerebellar alpha6 subunit, found in alcohol-hypersensitive rats. Dr. Mameli reported that ethanol affects gamma-aminobutyric acid (GABA) function by affecting neural circuits that influence GABA release. Dr. Parsons presented data from electrophysiological and microdialysis investigations that ethanol is capable of releasing GABA from presynaptic terminals. Dr. Morrow demonstrated that systemic ethanol increases neuroactive steroids in brain, the absence of which alters various functional responses to ethanol. Dr. Criswell presented evidence that the ability of ethanol to increase GABA was apparent in some, but not all, brain regions indicative of regional specificity. Further, Dr. Criswell demonstrated that neurosteroids alone and when synthesized locally by ethanol act postsynaptically to enhance the effect of GABA released by ethanol in a region specific manner. Collectively, this series of reports support the GABAmimetic profile of acutely administered ethanol being dependent on several specific mechanisms distinct from a direct effect on the major synaptic isoforms of GABA(A) receptors.  相似文献   
103.

Purpose

The purpose of the study was to evaluate the cause of death, risk of nonfatal complications, and relative outcomes with an enoxaparin versus unfractionated heparin strategy in ST-elevation myocardial infarction stratified using the Thrombolysis in Myocardial Infarction (TIMI) Risk Index (TRI).

Methods

We evaluated 30-day outcomes in 19,941 patients with ST-elevation myocardial infarction treated with fibrinolysis and unfractionated heparin or enoxaparin. Patients were categorized on the basis of prespecified ranges of the TRI [heart rate × (age/10)2/systolic blood pressure].

Results

There was a strongly graded increase in 30-day mortality with increasing TRI (1.2%-20.7%, P <.0001). The proportion of deaths due to mechanical causes (congestive heart failure, shock, and myocardial rupture) increased progressively with the TRI. There also was a significant positively graded association between the TRI and nonfatal heart failure or shock (0.4%-4.4%, P <.0001). In contrast, death resulting from recurrent ischemic events predominated in the lowest TRI group. The relative reduction in death/myocardial infarction with the enoxaparin strategy appeared inversely graded with the TRI. There was a 38% reduction in the lowest risk group (relative risk 0.62, 95% confidence interval 0.45-0.86) and a decrease in the relative benefit of enoxaparin with increasing risk index.

Conclusions

The TRI was a strong predictor of all-cause mortality in a broad population, with a positive association with the risk of death due to mechanical complications and an inverse association with deaths due to recurrent ischemia. The enoxaparin strategy was superior to unfractionated heparin in a majority of patients with ST-elevation myocardial infarction, except for the group at the highest risk for severe mechanical complications, in whom the 2 anticoagulant strategies showed similar results.  相似文献   
104.
Rising suicide rates are an increasing concern among military personnel. The interpersonal‐psychological theory of suicide proposes that three necessary factors are needed to die by suicide: feelings that one does not belong with other people, feelings that one is a burden on others or society, and an acquired capability to overcome the fear and pain associated with suicide. The current study tests the theory's proposal that acquired capability may be particularly influenced by military experience, because combat exposure may cause habituation to fear of painful experiences such as suicide. Utilizing clinical and nonclinical samples of military personnel deployed to Iraq, results of the current study indicate that a greater range of combat experiences predicts acquired capability above and beyond depression and post‐traumatic stress disorder symptoms, previous suicidality, and other common risk factors for suicide. Combat experiences did not, however, predict perceived burdensomeness or thwarted belongingness. The authors discuss how combat experiences might serve as a mechanism for elevating suicide risk and implications for clinical interventions and suicide prevention efforts. © 2010 Wiley Periodicals, Inc. J Clin Psychol: 66:1–13, 2010.  相似文献   
105.

Objective

A 2006 national survey of pediatric clerkship directors revealed that only 25% taught cultural competence, but 81% expressed interest in a validated cultural competence curriculum. The authors designed and evaluated a multi-modality cultural competence curriculum for pediatric clerkships including a validated cultural knowledge test.

Methods

Curriculum content included two interactive workshops, multimedia web cases, and a Cultural and Linguistic Competence Pocket Guide. Evaluation included a student satisfaction survey, a Nominal Technique Focus Group, and a validated knowledge test. The knowledge test comprised 6 case studies with 49 multiple choice items covering the curricular content.

Results

Of 149/160 (93%) students who completed satisfaction surveys using a 5-point Likert scale, >82% strongly agreed or agreed that the curricular intervention was a meaningful experience (93%), increased their understanding of the culture of medicine (91%), increased their knowledge of racial and ethnic disparities (89%) and core cultural issues (91%), and improved their skills in working with interpreters (90%) and cross-cultural communication (82%). Top strengths identified by a focus group (34 students) included learning about interpreters, examples of cultural practices, and raised cultural awareness. Pre- and post-knowledge test scores improved by 17% (p < .0001). After six administrations, the test achieved the target reliability of .7.

Conclusions

The authors successfully designed and validated a practical cultural competence curriculum for pediatric clerkships that meets the need demonstrated in the 2006 national survey.

Practice implications

This curriculum will enable pediatric clerkship directors to equip more graduates to provide culturally sensitive pediatric care to an increasingly diverse US population.  相似文献   
106.
BACKGROUND: If a validated questionnaire, when applied to patients reporting with symptoms of intermittent claudication, could adequately discriminate between those with and without peripheral arterial disease, GPs could avoid the diagnostic measurement of the ankle brachial index. AIM: To investigate the Edinburgh Claudication Questionnaire (ECQ) in general practice and to develop a clinical decision rule based on risk factors to enable GPs to easily assess the likelihood of peripheral arterial disease. DESIGN OF STUDY: An observational study. SETTING: General practice in The Netherlands. METHOD: This observational study included patients of > or =55 years visiting their GP for symptoms suggestive of intermittent claudication or with one risk factor. The ECQ and the ankle brachial index were performed. The prevalence of peripheral arterial disease, defined as an ankle brachial index <0.9, was related to risk factors using logistic regression analyses, on which a clinical decision rule was developed and related to the presence of peripheral arterial disease. RESULTS: Of the 4790 included patients visiting their GP with symptoms suggestive of intermittent claudication, 4527 were eligible for analyses. The prevalence of peripheral arterial disease in this group was 48.3%. The sensitivity of the ECQ was only 56.2%. The prevalence of peripheral arterial disease in a clinical decision rule that included age, male sex, smoking, hypertension, hypercholesterolemia, and a positive ECQ, increased from 14% in the lowest to 76% in the highest category. CONCLUSION: This study indicates that the ECQ alone has an inadequate diagnostic value in detecting patients with peripheral arterial disease. The ankle brachial index should be performed to diagnose peripheral arterial disease in patients with complaints suggestive of intermittent claudication, although our clinical decision rule could help to differentiate between extremely high and lower prevalence of peripheral arterial disease.  相似文献   
107.
BACKGROUND: Clinical correlates of HerpeSelect ELISA index values are poorly understood. OBJECTIVES: This study was designed to determine the effects of time of infection, test variability, and antibody avidity on index values. STUDY DESIGN: Sera (N=313) from 81 patients with new HSV-2 infections and 236 sera from 32 patients with long-standing (median 11.3 years) HSV-2 were tested by HerpeSelect HSV-2 ELISA. High positive, low positive and negative controls were run on 42 test plates to establish test variability. RESULTS: Index values tended to rise after infection, peaking a median of 9-10 weeks post-infection (range 8-323 days). Of 32 patients with established HSV-2 infections, 7 (22%) had at least one low index value (>1.1 to < or =3.5), and one had a transient seroreversion event. Test variability of index values was substantially lower than inter- or intra-patient variability. Median antibody avidity was higher in sera with high versus low index values in established infections, but unrelated to index value in patients with early infections. CONCLUSIONS: Index values or index value changes are not absolute indicators of early versus established HSV-2 infection or solely a function of test variability. Low antibody avidity may contribute to low index values once infection is established.  相似文献   
108.
Sarcocystis neurona is the primary causative agent of equine protozoal myeloencephalitis (EPM), a common neurologic disease of horses in the Americas. We have developed a set of enzyme-linked immunosorbent assays (ELISAs) based on the four major surface antigens of S. neurona (SnSAGs) to analyze the equine antibody response to S. neurona. The SnSAG ELISAs were optimized and standardized with a sample set of 36 equine sera that had been characterized by Western blotting against total S. neurona parasite antigen, the current gold standard for S. neurona serology. The recombinant SnSAG2 (rSnSAG2) ELISA showed the highest sensitivity and specificity at 95.5% and 92.9%, respectively. In contrast, only 68.2% sensitivity and 71.4% specificity were achieved with the rSnSAG1 ELISA, indicating that this antigen may not be a reliable serological marker for analyzing antibodies against S. neurona in horses. Importantly, the ELISA antigens did not show cross-reactivity with antisera to Sarcocystis fayeri or Neospora hughesi, two other equine parasites. The accuracy and reliability exhibited by the SnSAG ELISAs suggest that these assays will be valuable tools for examining the equine immune response against S. neurona infection, which may help in understanding the pathobiology of this accidental parasite-host interaction. Moreover, with modification and further investigation, the SnSAG ELISAs have potential for use as immunodiagnostic tests to aid in the identification of horses affected by EPM.  相似文献   
109.
Velo-cardio-facial syndrome/DiGeorge syndrome results from unequal crossing-over events between two 240-kb low-copy repeats termed LCR22 (LCR22-2 and LCR22-4) on Chromosome 22q11.2, comprised of modules, each of which are >99% identical in sequence. To delineate regions in the LCR22s that might contain hotspots for 22q11.2 rearrangements, we scanned the interval for increased rates of recombination with the hypothesis that these regions might be more prone to breakage. We generated an algorithm to detect sites of altered recombination by searching for single nucleotide polymorphic positions in BAC clones from different libraries mapped to LCR22-2 and LCR22-4. This method distinguishes single nucleotide polymorphisms from paralogous sequence variants and complex polymorphic positions. Sites of shared polymorphism are considered potential sites of gene conversion or double cross-over between the two LCR22s. We found an inverse correlation between regions of paralogous sequence variants that are unique to a given position within one LCR22 and clusters of shared polymorphic sites, suggesting that these clusters depict altered recombination and not remnants of ancestral single nucleotide polymorphisms. We postulate that most shared polymorphic sites are products of past transfers of DNA information between the LCR22s, suggesting that frequent traffic of genetic material may induce genomic instability in the two LCR22s. We also found that gaps up to 1.5 kb long can be transferred between LCR22s.  相似文献   
110.
Renal dysfunction is a major determinant of outcome after HTx. Using a large, multi-institutional database, we sought to identify factors associated with late renal dysfunction after pediatric HTx. All patients in the PHTS database with eGFR ≥60 mL/min/1.73 m(2) at one yr post-HTx (n = 812) were analyzed by Cox regression for association with risk factors for eGFR <60 mL/min/1.73 m(2) at >1 yr after HTx. Freedom from late renal dysfunction was 71% and 57% at five and 10 yr. Multivariate risk factors for late renal dysfunction were earlier era of HTx (HR 1.84; p < 0.001), black race (HR 1.42; p = 0.048), rejection with hemodynamic compromise in the first year after HTx (HR 1.74; p = 0.038), and lowest quartile eGFR at one yr post-HTx (HR 1.83; p < 0.001). Renal function at HTx was not associated with onset of late renal dysfunction. Eleven patients (1.4%) required chronic dialysis and/or renal transplant during median follow-up of 4.1 yr (1.5-12.6). Late renal dysfunction is common after pediatric HTx, with blacks at increased risk. Decreased eGFR at one yr post-HTx, but not at HTx, predicts onset of late renal dysfunction. Future research on strategies to minimize late renal dysfunction after pediatric HTx may be of greatest benefit if focused on these subgroups.  相似文献   
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